Treatment of ores.



N. H. M. DEKKER.

TREATMENT OF ORES.

APPLIOATION FILED 211F115, 1911.

l,@75,4Q9, Patented Oct. 14, 1913.

NICOLAS HENRI MARIE DEKKER, or PARIS, FRANCE.

TREATMENT OF GEES.

ora-ace.

Specification of Letters Patent.

Patented (lot. 3141, 1913.

Application filed September 15, 1911. Serial K0. 649,549.

To all whom it may concern:

'Be it known that I, NICOLAS HENRI' MARIE DEKKER, citizen of the Republic of France, and a resident of Paris, France, have invented new and useful Improvements in or Relating to the Treatment of Ores, of which the following is a specification.

This invention relates to a process for the treatment of sulfureted, oxidized, carbonated and other ores.

When a sulfid is placed in the presence of an acid, even at a high temperature, the reaction of the ore is very slow, and the same applies when the acid is replaced by an alkaline salt. But when two substancesacid and alkaline or metal salt-are combined in given proportions, and the mixture in question, suitably heated, brought into the presence of the ore in question, the reaction is complete and almost immediate, if care is taken to mix or stir the different substances brought together. This miXture acts as a powerful reagent, and dissociates all the sulfates, polysulfates, arsenids, oxids and carbonates, and combines with the metals contained in the ores and releases the metalloids such as sulfur, arsenic, oxygen and carbon, according to circumstances. As a rule, the salt used is a sulfate, and the acid is sulfuric acid. Nevertheless, it has been found that a polysulfate acts better than a monosulfate, and with the majority of the ores the best result is obtained by means of a pentasulfate, which obviously does not preclude the use of other polysulfates. But this treatment would not be sufficient, as it would not admit the use as reagents of any but sulfates soluble in sulfuric acid, while for practical purposes it must also admit of the use, as reagents, of a ny sulfates, including even those insoluble in sulfuric acid. To that end, it is sufficient to form with the sulfates insoluble or slightly soluble in sulfuric acid, double sulfates soluble in the said acid. This, iron sulfate which gives rather a poor result when it is used alone in the state of pentasulfate or polysulfate, gives a very good result if, before converting it into pentasulfate or polysulfate, it is combined for instance with sulfate of soda or of magnesium. The combination of the sulfates, even the soluble ones, may be advantageous in many cases. Thus magnesium sulfate combined with another sulfate, such as sulfate of soda and then converted into a pentasulfate, also gives an excellent result for releasing the sulfur contained in a sulfid; it is better than pentasulfate of magnesium and pentasulfate of soda used separately.

For carrying out the process it is necessary to establish a classification based on the chemical properties of metals and isomorphism of their principal salts. The classification below complies with that requirement 1st group. Alkaline metals: lithium, potassium, sodium, rubidium, caesium, etc., as well as silver and thalium which are monovalent and the salts of which, as regards thalium, are isomorphous with the salts of potassium, and as regards silver, the azotate or nitrate is isomorphous with that of potash.

2nd group. Metals of alkaline earths: calcium, barium strontium, to which is added lead, the sulfates and carbonates of which are isomorphous with the corresponding salts of calcium, barium and strontium.

3rd group. Sulfates of the magnesium series: (1) magnesium, zinc, cadmium, etc.; (2) sulfates of isomorphous protoxids of sul fate of magnesium, chromium, iron cobalt, nickel, manganese, etc.

4th group. Aluminium, gallium,'indiu1n, etc.

5th group. Tin, antimony, bismuth, titanium, zirconium, etc.

6th group. Copper, mercury.

7th group. Gold.

8th group. Platinum, iridium, osmium and all the metals found in conjunction with platinum.

According to the ores to be treated, sulfates of the metals of one of'the groups, or of any two groups, can be combined together in the state of polysulfates or double pentasulfates for instance: soda-magnesia soda iron, iron magnesia, zinc magnesia, lead-copper, aluminium-soda, etc. By this process good reagents are therefore obtained with double pentasulfates, and it is thus possible to use sulfates which alone are insoluble in sulfuric acid.

For carrying out the process, the polysulfate, whether a pentasulfate or any other, is placed into a tank made of iron or other suitable material, which is heated to about 80 C. by means of a suitable furnace. The ore to be treated, suitably enriched, is then added, and the whole stirred. The reaction which takes place gradually, generates in the interior a greater heat than pose.

' escape.

treatment.

that supplied by the outer furnace, and at the end of about half an hour, the whole of the contents is boiling violently. The reagent seizes upon the simple metal bodies and releases the metalloids which escape through an opening provided for the pur- When it is desired for instanc to treat a carbonated ore, carbonic acid will In the case of a sulfid, the Whole of the sulfur contained in the ore is released in the state of flowers of sulfur, and is brought through a conduit into a suitable tank where it is collected. The stoppage in the release or escape of the metalloid is a proof that the reaction is completed, and that there remains in the tank only the reagent combined with the metal or metals contained in the initial charge of ore, the whole in the form of sulfates which form the reagent added to the sulfates of the metals contained in the ores of the charge. All the sulfates being soluble in water, either in a simple or in a combined state, as has been explained, Water is introduced into the tank, and the solution withdrawn through an opening suitably arranged near the bottom of the tank. The solution is deprived of its metal or metals either by electrolysis or by precipitation, and the rest of the solution is then evaporated, the'reagent being recovered in its original state, and ready to be used for a fresh treatement.

The sulfates previously mentioned are of coursenot the only salts suitable for ca rrying out the process. Speaking generally, any alkaline sulfate or sulfate of alkaline earth, or even any metal sulfate, could be used. Moreover, in certain cases it may be necessary to use multiple pent-asulfates in place of double pentasulfates. This obviously depends on the nature and the com plexity of the ores to be treated.

The accompanying drawing shows by way of example in vertical section, a construction of apparatus suitable for the The apparatus comprises a furnace at on which is placed an iron vat Z) adapted to be heated. This vat is surmounted by alid c resting in a groove d forming the upper edge of the vat, so as to form a hydraulic joint or seal. At thebottom of the said vat is longitudinally arranged a spindle 6 provided with blades f and carrying outside a pulley g by means of which it can be rotated frgm a line shaft or suitable motor. On the lid 0 which is of conical shape, is arranged a hopper h, the bottom of which is constituted by a slide 71 which can be opened or closed. The cover' a is surmounted at its upper end by a completely closed chamber 7' from the upper face of which descends a cone is passing into the cover and leaving between its circumference and the upper edge of the latter, sufficient space for the passage of the substances generated in the apparatus. During the operation, the blades f insure the mixing of the ore and the reagent, and in the case of the treatment for instance, of sulfids, the sulfur is discharged into the chamber 7' on the bot-tom of which it spreads and whence it can be easily extracted through doors or other suitable devices.

In order to introduce the ore, it is poured into the hopper h, and the valve z is then caused to slide so that the ore drops into the vat b. The orifice of the hopper h is then closed by the valve 2' during the opera tion of the apparatus.

Having now particularly described and ascertained the nature ofmy said invention and in what manner the same is to be performed, I declare that what I claim is:

The process for the treatment of ores of the character described, which consists in mixing with the dry ore in a closed container, a reagent comprising a metallic sulfate and concentrated sulfuric acid, maintaining the temperature of the mixture above normal to preserve liquefaction of the reagent, agitating the mass until the non-metallic ore constituents are dispelled, adding water to the residue to form a solution, and separating the metals from the solution thus formed.

In testimony whereof I aiiix my signature in presence of two witnesses.

H. C. Coxn,

JULIEN CAVERNE. 

